An arrayed waveguide grating (AWG) device associated with a demultiplexer may provide for communication of multiple channels of an optical signal. For example, a high-speed multichannel receiver of a network node (e.g., a 100 Gigabits per second (Gbps) data rate capacity receiver, a 200 Gbps data rate capacity receiver, a 400 Gbps data rate capacity receiver, and/or the like) may couple to multiple output waveguides of an arrayed waveguide grating of a coarse wavelength division multiplexing (CWDM) demultiplexer or another type of demultiplexer to receive information from a high-speed multichannel transmitter of another network node. The high-speed multi-channel receiver may include a photodiode array to receive optical signals from the multiple output waveguides of the arrayed waveguide grating. In this case, each waveguide of the multiple output waveguides may be optically coupled to a corresponding photodiode of the high-speed multi-channel receiver.
The multiple output waveguides of the arrayed waveguide grating device may be multi-mode waveguides to ensure a flat-top response in the photodiodes. The flat-top response may refer to an intensity of optical signals received by each photodiode at a set of wavelength ranges being relatively even (e.g., a peak intensity in the set of wavelength range may be within a threshold percentage of a minimum intensity in the set of wavelength ranges). The multiple modes may refer to multiple different distributions of intensities that may be associated with a wavelength of an optical signal, a temperature at which the optical signal is provided, and/or the like. By achieving the flat-top response for the multiple output waveguides, the multi-mode waveguides may enable the photodiodes of the high-speed multi-channel receiver to efficiently receive optical signals.